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Yamaha 2024 line up …

Was there confirmation somewhere that the 255 was coming with a 4-blade impeller? I thought I read someone say that, but I can't find anything on it.
 
Was there confirmation somewhere that the 255 was coming with a 4-blade impeller? I thought I read someone say that, but I can't find anything on it.

I think the one post said only the 1.9 engines got them and the 255 still has the 1.8’s.
 
After watching those videos......I challenge anyone to tell me a jet isn't as maneuverable as something else. The best part is, the only capability the joystick has over the regular twin engines is the ability to split the steering between jets, otherwise the SX210 has the same control as that setup.

Cool stuff.
 
After watching those videos......I challenge anyone to tell me a jet isn't as maneuverable as something else. The best part is, the only capability the joystick has over the regular twin engines is the ability to split the steering between jets, otherwise the SX210 has the same control as that setup.

Cool stuff.

That’s a great video thanks for posting!
 
This is a great video going over the details of the new engines if anyone is interested. Around 17 minutes is where the details start.
 
No details/ info of the removal of Lead from rod bearings ? ?? what material/element were they replaced with ? Lead is a great material for a bearing and partly reason 1.8s were so solid for all these years ...
 
After watching the 1.9L video, the piston and head changes to me appear to be setting up this engine to be a better candidate for supercharging. The un shrouded valves and bigger combustion chamber, and what appears to be a higher compression piston, as well as the reduction of overlap as the overlap is designed to promote cleaning, but you don’t need as much overlap if your intent is forced induction.

The older 1.8L was originally designed with the intent to make max power without forced induction, and the addition of super charging came later (? That’s my impression) as a way to boost power. Having said that, I think what we may be looking at is higher power from the SC’ed 1.9L over the 1.8L, I’m going to guess the power will be increased to 300 hp or slightly more so that Yamaha will be the HP king over Rotax powered Scarabs and their 300 hp engines.

I also see that the crank sensor / gear was improved to keep the over rev peak from being so great eliminating a 400 rpm cycle, in addition to keeping the surging and porpoising from happening this should also help with the SC reliability when the pump comes unhooked then hits water again, thereby reducing clutch wear and breakage.

Cooling upgrades in the block are a good thing and allow better temperature control along with controlling the heat in higher power configurations and as the young man stated, allows better control of detonation.

Turbocharging; taking advantage of the efficiency, no parasitic loss, less affected by increases in density altitude. The two guys mentioned that the parasitic loss differences between SC and TC are small but it’s there, from my experience the parasitic loss of a SC is 7-10%, going with the most liberal estimate of 10% in a 250 hp engine, that frees up 25 hp alone without increasing the stress on the same engine, the efficiency increase also allows Yamaha to claim the reduction in emissions as part of their environmental virtue signaling. The extra heat that needs to be dealt with from a TC application is readily gotten rod of via the fact there is an unlimited supply of water available to carry that heat away. AND, if it was a compound system, meaning a SC and a TC, the SC provides the instant power while the TC spools up, once the TC spools up and starts making boost, it takes over all of the boost duties and the parasitic losses of the SC goes away by virtue of there being no pressure differential across the SC, also know as having your cake and eating it.

Time will tell, but Yamaha could have some big surprises ahead.
 
The older 1.8L was originally designed with the intent to make max power without forced induction, and the addition of super charging came later (? That’s my impression) as a way to boost power. Having said that, I think what we may be looking at is higher power from the SC’ed 1.9L over the 1.8L, I’m going to guess the power will be increased to 300 hp or slightly more so that Yamaha will be the HP king over Rotax powered Scarabs and their 300 hp engines.

Except that there is a new Rotax engine for 2024, https://jetboaters.net/threads/new-325-hp-rotax-for-2024.42465/

Scarab hasn’t released their 2024 boats yet, but, one would think the new 325 hp Rotax would be an option.

Jim
 
I hope the next redesign of the 25' is like the 22' so the bimini top does not need a cage. I really like how I can roll up my bimini and just have the wake tower.
 
I hope the next redesign of the 25' is like the 22' so the bimini top does not need a cage. I really like how I can roll up my bimini and just have the wake tower.

I would anticipate big things for the redesign of the 25'. Have a funny feeling it is going to have some very good things. When that day comes.
 
The older 1.8L was originally designed with the intent to make max power without forced induction, and the addition of super charging came later (? That’s my impression) as a way to boost power.

The 1.8L HO and 1.8L SHO were released alongside each other in 2008 in the FX Cruiser HO and SHO and FZR/FZS SHO in 2009. The boats were still running the MR-1 and didn't have the 1812cc engine until 2010 IIRC. The 1.8L engine was not designed as a NA motor with supercharging thrown in as an after thought especially since Seadoo was running SCers in the GTX since 2003 and RXP since 2004.
 
I got a 2024 AR250 in yesterday and was able to get it out on the water today. Here are my impressions of the new motors:

- The engines definitely have more power than the previous 1.8. It was very noticeable on take off and in the mid range. We had two full size adults on board and hit 51 mph. There was no cavitation on a full power take off from standstill and the boat really hooked up well. I'm very pleased.

- Noise wise the boat is certainly quieter. At 30mph I was able to hold a normal level conversation with my tech. Of course there's still wind noise but the drone of the engines is significantly less.

- Vibration levels have been drastically improved and honestly that was my and my tech's biggest take aways from our outing this morning. There was not rattling throughout the boat and the steering wheel and throttles felt absolutely solid and still. It really feels like an entirely different boat.

I didn't do much efficiency testing but with a full tank of fuel and 2 large men aboard we were getting just 12.7gph at 29/30mph. Not too shabby. Happy to answer any questions so fire away.
 

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I got a 2024 AR250 in yesterday and was able to get it out on the water today. Here are my impressions of the new motors:

- The engines definitely have more power than the previous 1.8. It was very noticeable on take off and in the mid range. We had two full size adults on board and hit 51 mph. There was no cavitation on a full power take off from standstill and the boat really hooked up well. I'm very pleased.

- Noise wise the boat is certainly quieter. At 30mph I was able to hold a normal level conversation with my tech. Of course there's still wind noise but the drone of the engines is significantly less.

- Vibration levels have been drastically improved and honestly that was my and my tech's biggest take aways from our outing this morning. There was not rattling throughout the boat and the steering wheel and throttles felt absolutely solid and still. It really feels like an entirely different boat.

I didn't do much efficiency testing but with a full tank of fuel and 2 large men aboard we were getting just 12.7gph at 29/30mph. Not too shabby. Happy to answer any questions so fire away.

That all sounds fantastic, I was itching to go after the 255 FSH Sport H this year, but maybe I can hold my trigger finger another year and perhaps they'll have SVHO 1.8's in them next year... that would be worth waiting for I think.
 
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